Comparison of test methods for mould growth in buildings

The purpose of this work is to compare a range of test methods and kits for assessing whether a building structure is infested by mould fungi. A further purpose of this work is to evaluate whether air-based methods for sampling fungal emissions provide information qualifying decisions concerning renovation needs. This is of importance when hidden surface testing would require destructive measures and subsequent renovation. After identifying available methods on the Danish market for assessing mould growth in dwellings, a case study was conducted to test the usefulness of the methods in four dwellings of different typology and with or without known mould infestations. In each dwelling seven methods were used in parallel. The criteria for choosing the different methods were that they had to be nondestructive, relatively quick and easy, and frequently used by building professionals. The chosen methods measure different aspects relating to mould growth and vary in selectivity and precision. The two types of air samples indicated low levels of mould growth, even where the results of the other methods indicated high to moderate growth. With methods based on culture and DNA testing some differences in the species that each identified were apparent. In conclusion we found visual and olfactory inspection to be quite indicative of mould growth while none of the surface tests gave the complete representation as stand-alone tests. The air sampling methods seemed only to react to very comprehensive infestation with fungi.